There are a variety of slip designs in use and various techniques are used to retain the slips to a housing so that upon release of the packer or bridge plug the slips stay connected to the housing so that the slips come out in tandem with the housing. Most of these designs are concerned with limiting radial movement of slips pushed out radially during the set. Some examples of designs involving retaining movement of slips are: U.S. Pat. No. 8,561,687 (FIG. 6A item 605); US 2016/0251922 (FIG. 5A item 512 slip ring retainer); U.S. Pat. No. 5,046,557 (FIG. 3 items 38 and 52); U.S. Pat. No. 6,119,774 (FIG. 1 item 12); and U.S. Pat. No. 5,727,632 (FIG. 1d item 80).
As described below in an effort to reduce the length of a packer or plug there needed to be enough lost motion among the components so that the lock holding the packer or plug set position could release first before any movement to undermine an upper slip was undertaken. This was accomplished with added length to an opening that retains a transverse portion of a T-shaped slip so that enough lost motion for the mandrel could be had before grabbing the upper slip and pulling it uphole and away from its associated slip cone. The problem that can occur in such a modified design is that on the way out of the hole the packer or plug could run into larger tubulars than the size of tubular for which the packer or plug was intended to be set. When this happens the slip can slide down far enough to move out of its guides that are located on opposed sides. The present invention provides a travel stop to halt such movement before the slip guides can exit their guide channels. If that exit were to happen in a larger tubular then the slip can come out of the slip ring and can jam the packer or plug on the way out of the hole forcing a milling job. As an alternative travel stop the slip ring can have retainers that limit radial movement of the transverse portion of the T-shaped slip so that the slips will come out with the slip ring and will be incapable of falling out. This latter approach is more expensive to manufacture than the former solution but may be preferred in some cases. Those skilled in the art will better understand the underlying packer design and the slip travel stop feature applied to such a design from a review of the description of the preferred embodiment and the associated drawings while recognizing that the full scope of the invention is to be found in the appended claims.
Setting and unsetting of downhole tools is a common activity in the hydrocarbon exploration and recovery industry. Also due to the many different kinds of tools to be set and unset, there are various iteration of the setting and unsetting arrangements to support the goal. While many exist and function well for their intended purposes, it is also always a desire in the industry to improve efficiency, reduce cost and or improve function of all downhole tools. Arrangements then that reduce length, reduce unwanted motion in favor of facilitating wanted motion and combining functions are all desirable to the art.